function withData (param) {
  return param < 10 ? '0' + param : '' + param;
}
function getLoopArray (start, end) {
  start = start || 0;
  end = end || 1;
  let array = [];
  for (let i = start; i <= end; i++) {
    array.push(withData(i));
  }
  return array;
}
function getMonthDay (year, month) {
  let flag = year % 400 === 0 || (year % 4 === 0 && year % 100 !== 0); let array = null;

  switch (month) {
  case '01':
  case '03':
  case '05':
  case '07':
  case '08':
  case '10':
  case '12':
    array = getLoopArray(1, 31);
    break;
  case '04':
  case '06':
  case '09':
  case '11':
    array = getLoopArray(1, 30);
    break;
  case '02':
    array = flag ? getLoopArray(1, 29) : getLoopArray(1, 28);
    break;
  default:
    array = '月份格式不正确，请重新输入！';
  }
  return array;
}
function getNewDateArry () {
  // 当前时间的处理
  let newDate = new Date();
  let year = withData(newDate.getFullYear());
  let mont = withData(newDate.getMonth() + 1);
  let date = withData(newDate.getDate());
  let hour = withData(newDate.getHours());
  let minu = withData(newDate.getMinutes());
  let seco = withData(newDate.getSeconds());

  return [year, mont, date, hour, minu, seco];
}
function dateTimePicker (startYear, endYear, date) {
  // 返回默认显示的数组和联动数组的声明
  let dateTime = []; let dateTimeArray = [[], [], [], [], [], []];
  let start = startYear || 1978;
  let end = endYear || 2100;
  // 默认开始显示数据
  let defaultDate = date ? [...date.split(' ')[0].split('-'), ...date.split(' ')[1].split(':')] : getNewDateArry();
  // 处理联动列表数据
  /* 年月日 时分秒*/
  dateTimeArray[0] = getLoopArray(start, end);
  dateTimeArray[1] = getLoopArray(1, 12);
  dateTimeArray[2] = getMonthDay(defaultDate[0], defaultDate[1]);
  dateTimeArray[3] = getLoopArray(0, 23);
  dateTimeArray[4] = getLoopArray(0, 59);
  dateTimeArray[5] = getLoopArray(0, 59);

  dateTimeArray.forEach((current, index) => {
    dateTime.push(current.indexOf(defaultDate[index]));
  });

  return {
    dateTimeArray: dateTimeArray,
    dateTime: dateTime
  };
}
module.exports = {
  dateTimePicker: dateTimePicker,
  getMonthDay: getMonthDay
};